Dr. Ahmad Redaa
2024-10-28
Who was Alfred Wegener?
German meteorologist and geophysicist who proposed the
Continental Drift Theory in 1912.
Continental Drift Theory
Wegener suggested that continents were once part of a supercontinent
called Pangaea and have since drifted apart.
Evidence Supporting Continental Drift
Initial Reception:
Skepticism due to lack of a plausible mechanism for continental
movement.
Alfred Wegener a few years before his death in 1930. Source: Steven, E. (2015)
Static Earth Models:
Early theories assumed Earth’s features were fixed and
unchanging.
Continental Movement Debates:
Wegener’s theory sparked discussions about the possibility of
continental and oceanic movement.
The distribution of several Permian terrestrial fossils that are present in various parts of continents that are now separated by oceans. Source: Steven, E. (2015)
What is it?
Wegener’s theory that continents were once joined as Pangaea and have
drifted apart over millions of years.
Key Evidence for Continental Drift:
What is it?
Theory that new oceanic crust forms at mid-ocean ridges
and moves outward, driving the movement of tectonic plates.
Key Concepts:
Evidence for Seafloor Spreading:
Pattern of sea-floor magnetism off of the west coast of British Columbia and Washington. Source: Steven, E. (2015)
What is it?
A theory that Earth’s lithosphere is divided into plates that move over
the semi-fluid asthenosphere, shaping Earth’s surface.
Key Components:
Evidence Supporting Plate Tectonics Theory:
The layers of the tectonic Earth, (Source: Jain, S. (2014))
The Ocean–Ocean convergence, (Source: Jain, S. (2014))
The Ocean–Continent convergence, (Source: Jain, S. (2014))